Light bulb



FIG. 1 is an isometric view of a light bulb.

FIG. 2 is a front view of the light bulb of FIG. 1 .

FIG. 3 is a back view of the light bulb of FIG. 1 .

FIG. 4 is a left view of the light bulb of FIG. 1 .

FIG. 5 is a top view of the light bulb of FIG. 1 ; and,

FIG. 6 is a bottom view of the light bulb of FIG. 1 .

The broken-line disclosure represents portions of the light bulb which form no part of the claimed design. 

CLAIM The ornamental design for a light bulb, as shown and described. 